1. Field of the Invention
The present invention relates generally to a steering system for vehicles. More particularly, the invention relates to a steering system for a vehicle including a steering wheel and front and rear wheels, in which the front and rear wheels are steerable in the same and opposite directions relative to each other in accordance with the steering angle of the steering wheel.
2. Description of Relevant Art
There have been proposed steering systems for vehicles, such as disclosed in Japanese Patent Application No. 56-118698, in which a rear wheel steering sub-system includes left and right rear wheel steering tie rods directly or indirectly connected to and supported by an off-centered pin arranged to be rotatable with rotation taken out from a front wheel steering sub-system. The left and right rear wheels are thus capable of being steered both in the same and opposite directions with respect to the left and right front wheels in accordance with the steering angle of a steering wheel. The rotation from the front wheel steering sub-system is taken out through a linkage having a rotary member provided with the aforesaid off-centered pin, which rotates in a crank-like manner while functioning to steer the rear wheels as described hereinabove, i.e., permitting the rear wheels to be steered in the same direction as the front wheels for relatively small steering angles of the steering wheel and in the opposite direction for relatively large steering angles thereof. Accordingly, there is provided favorable maneuverability characteristics when the vehicle is moving at relatively high speeds, as well as favorable turning characteristics due to relatively small turning radii, such turning characteristics being particularly advantageous with respect to effecting a U-turn or when parking, etc.
In such types of steering systems for vehicles, it is desirable to maximize the freedom of design in setting the relation between the steering wheel steering angle and the turning curvature of the vehicle, so as to accommodate various driving tastes relating to steering characteristics when rounding curves or corners or driving at high speeds.
The present invention provides the aforesaid desired design freedom in a steering system for vehicles.